The White House announced today that 28 companies in the private sector have pledged their commitment to closing the gender pay gap for their employees—fitting for Women’s Equality Day.

The companies range across multiple industries including Apple, Delta Air Lines, Hilton, Ikea and more.

In the United States, women working full time earn an average of 79 cents for every dollar men make, according to Census data. Black women are paid 63 cents and Latina women 56 cents compared to every dollar paid to white men.

Several recent studies have confirmed the existence of the wage gap across industries and employment levels.

More than 50 companies have signed the White House Equal Pay Pledge, which has been in the works for some time now. In January, President Obama signed an executive order requiring businesses with more than 100 employees to report their wage data broken down by race and sex to the U.S. Equal Employment Opportunity Commission.

Each company that signed today included a personal pledge. Some excerpts are below:

Apple:

Equal work deserves equal pay. This past year, Apple looked at the total compensation for U.S. employees and closed the gaps we found. We’ve achieved pay equity in the United States for similar roles and performance. Women employees at Apple earn one dollar for every dollar male employees earn.

Facebook:

Facebook is a longtime supporter of equal pay. We regularly review our compensation practices to ensure pay equity, and have done so for many years. We complete thorough statistical analyses to compare the compensation of men and women performing similar work. As such, we are proud to share that at Facebook, men and women earn the same. We encourage efforts to establish methods to close the wage gaps around the world.

Ikea:

We know that each individual adds value to the team, and we are committed to creating an inclusive work environment that encourages our diverse and competent co-workers to be themselves, to apply their unique perspectives at work, and to assume responsibility for our growth. In addition to being the right thing to do, creating this environment also improves our business results and strengthens our competitiveness.